feat: Migrates the deckgl-points sample to js-api-samples.

[willum070]

This PR does the following things:

• Migrates deckgl-points to js-api-samples.
• Adds an interface declaration for EarthquakeProperties.

[snippet-bot]

Here is the summary of changes.

You are about to add 3 region tags.

• samples/deckgl-points/index.html:7, tag maps_deckgl_points
• samples/deckgl-points/index.ts:7, tag maps_deckgl_points
• samples/deckgl-points/style.css:17, tag maps_deckgl_points

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